There are two translation summer schools (to my knowledge) running in the UK this summer. Both of them have had excellent reports from my students in previous years.
The British Centre for Literary Translation Summer School in Norwich will offer workshops with Dutch, German, Italian, Korean and Norwegian this year, as well as English creative writing workshops, and prose and poetry translation workshops open to anyone translating into English. A feature of the Summer School is the opportunity to work with the author of the source text as well as with an experienced translator as workshop leader.
The Translate in the City summer school in London will run with the list of languages and tutors as below.